Speed indicator with recording devices, especially for motor cars



p 1933- i A. SCHMELCHER 1,928,505

SPEED INDICATOR WITH RECORDING DEVICES, ESPECIALLY FOR MOTOR CARS Filed July 21, 1.930 2" Sheets-Sheet 1 R Sept. 1933. A. SCHMELCHER 1,928,505

SPEED INDICATOR WITH RECORDING DEVICES, ESPECIALLY FOR MOTOR CARS Filed July 21, 1950 2 Sheets-Sheet 2 Patented Sept. 26, 1933 I UNITED STATES SPEED INDICATOR WITH RECORDING DE- VICES, ESPECIALLY FOR MOTOR CARS Alexander Schmelcher, Kiel, Germany Application July 21, 1930, Serial No. 469,527, and in Germany March 5. 1930 2 Claims. (CL 234-31) This invention relates to a positively actuating speedometer for motor cars, in which the increase and decrease of the speed is indicated in stages and can be read and controlled both by the driver and also observed on the front and rear part of the vehicle, and especially to such speedometers, in which centrifugal governors are employed. These centrifugal governors mostly consist of springs loaded with weights and fastened at their ends on rings, which mutually slide on a shaft, rotated from the driving mechanism of the motor, and thus actuate the indicator. They all work symmetrically, so that the contacts are directly influenced and, owing to the fact that blade springs are used, a certain tiredness occurs, which leads to fracture of the springs, as they are continually moved when the speed changes.

This-invention overcomes this objection in that the weights are arranged as direct controlling elements between the current supply bars and the current collecting contacts in such a manner that both the lamps and the recording device connected up in the lamp circuit are directly actuated by the weights, so that the weights swingout unsymmetrically, as they act on spiral springs differently loaded, which are protected against overpressure by spacing sleeves.

, Consequently not only all oscillating differences more quickly, because each driver will be informed of the speed of the approaching or passing car.

An embodiment of the invention is illustrated by way of example in the accompanying drawings in which:

Fig. 1 shows the transmitting and controlling apparatus in longitudinal section.

Fig. 2 is across section through the contact I weights.

Fig. 3 is a plan view of the contact weight in the direction of the arrow shown in Fig. 2.

Fig. 4 shows the contact weight in side elevation.

Fig. 5 is a top'plan view of the weight.

Fig. 6 shows the wiring diagram with the possible for the motor cars to follow one another lamps and the recording device seen from the front, the cover being removed.

Fig. '7 is a side view of the lamps and of the recording device.

The speed indicating arrangement consists of 9. transmitting apparatus (Figs. 1 to 8) the source of electric current (Fig. 6) and the recording apparatus (Figs. 6 and 7). The transmitting or controlling apparatus consists of a casing 1, in which a shaft 2 is rotatably mounted on ball bearings 3 and connected and driven by the tachometer wire or a similar flexible shaft of the car. On this shaft 2 the carrying element 4 is mounted in the two armed contact holders 5 and 6, of which the current supply bars 7 and the collector contacts 8 are arranged on the inner side in an insulating plate 9 and insulating sleeve 10, between which the oscillating contact weights 11 slide, whereas the current supply terminals 54 and current collector terminals 12 are situated on the outer sde of the contact holders 5 and 6.

The contact weights 11 slide on two guide bars 13 fastened in the carrying element 4 so that it is impossible for them to twist, and towards the outside they are cushioned by two springs mounted on each guide rod 13, .between which springs spacing sleeves 16 are arranged. Thesprings '14 and 15 are adjusted for each individual weight in such a manner that the weights swing out difierently, according to the settings of the springs so that the springs 14 and then the springs 15 come into operation each time through the centrlfugal force of the contact weights 11. In order to obtain the smallest possible diameter, the contact weights 11 engage in cavities of the control element 4, the springs 14 and the spacing .sleeves 16 in the cavities of the contact weight 11. In the centre of the contact weights 11 the spring loaded slidng contacts 18 are mounted on an insulating sleeve 17. On the ends of the guide bar 13 nuts 19 are arranged, provided with spacing sleeves and with securing slots, in which a bar of the washer 20 engages so that the nuts 19 cannot work loose. Below the carrying element 4 an insulating drum 21 is fastened on the shaft 2, and on which the collector rings 22, 23, 24 and 25 for the slip or collector contacts 26, 2'7, 28 and 29 are mounted. The current supply wire 30 connects the collector ring 22 with the current supply bar 7. The collector rings 23, 24, 25 are each connected with the actual current collecting terminals 12 by the wires 31, 32 and 33 respectively. The necessary working current is taken from the car battery or from the illuminating dynamo 34, to which the recording device is also connected which is connected to the collector wires 35, 36, 37 of the transmitting or controlling apparatus.

The recording device is composed of two drums 38 and 39, over which a paper band, not shown, is wound so that it unwinds from one drum 38 and winds onto the other drum 39. This latter drum 39 is actuated by a current coil 40, which consists of two or more separate current circuits, analogous to the lamp groups in such a manner that an iron core 41 is lifted more or less by the current of the group of lamps switched in, ac-

cording to the speed travelled so that it acts on the loose bevel wheels 42, 43, by means of a connecting rod and ratchet in such a manner that the bevel wheel 42 is shifted when the iron core 41 rises, whereas the other bevel wheel 43 runs idle. On the idle core 41 descending, the bevel wheel 43 is shifted and the bevel wheel 42 runs idle. By this means the bevel wheel 44 and therefore the drum 39 will always rotate in one and the same direction during all movements of the iron core 41. The tracing point holder 46 is also mounted on the axle 45, which carries the loose bevel wheels 42 and 43. The tracing point is pressed against the paper by a spring 48, so as to trace by the point 47, the travelling speed. The point 47 is loaded by a suitably balanced weight so that in the event of a sudden collision between two cars or the like, a hole is punched in the paper by the tracing point 47 and thus the speed travelled at the time of the impact is recorded. Consequently a slot-like depression is provided in the paper support 49, which depression enables the point to perforate the paper. In order to always stretch the paper, a hand screw 50 is provided on the drum 38, which is further braked by a spring and brake disc.

The operation, when travelling is as follows:

When the vehicle starts, the transmitting apparatus, owing to its construction, remains in inoperative position up to 20 kilometers. If the speed increases, the contact weights 11, owing to the centrifugal force, shift on the guide rods 13 and close consecutively the contacts 8 so that both at the rear, as also in front of the car and on the dash board of the driver's seat the same signal lamps 51, 52 and 53 are illuminated, and the current'coils 40 of the recording apparatus are actuated both dependently as also independently of the lamps (in series, in parallel or in series-parallel). The signals are adapted to the new traflic regulations, a green light, lamps 51 appearing from 20 to 30 kms. two lamps 51 and 52, greenyellow light, appearing at a speed of 40 to 42 kms., the yellow lamps 52 at speeds of 42 to 60,the'lamps 52 and 53, yellow-blue between 60 .and 65 kms. and the blue lamps 53 at speed exright hand contact weight 11 (Fig. 1) moves so far towards the right, that the first contact 8 makescontact with the contact bar 7. The current flows from the battery or some other source of current 34 to the collector ring 22, through the wire 30 to the contact bar 7, through the contact 18 of the contact weight 11 to the contact 8, connected with the collector ring 23 by the wire 31, through the collector ring 23 and contact 27, through the wire 35 to the coil 40, and thence to the green lamp 51 on the drivers seat, after which it passes back to the coil 40 and onto the lamps 51 at the front and rear of the car, whence it flows back to the source of current 34. Therefore the coil 40 will be actuated, when the current flows through the individual groups of lamps, according to the actual speed so that the iron core 41 is first raised in the first circuit, thereby at the same time setting the recording device in operation. Moreover all lamps 51 are caused to illuminate. The same operation occurs at the next higher speed etc, only.other contact positions are assumed by the contact weights 11 so that the coil 40 lifts the iron core into the next stage of the following group of lamps so that other lamps are illuminated. As the speed reduces, the changes occur in the contrary rotation.

It may be mentioned that the contact weights 11 can be adjusted for other speeds and that no vacillating of the light signals occurs between the several stages, so that differences in speeds within the adjusted stages are not registered. Instead of a two armed carrying element 4 with two contact weights 11 naturally threefouror more-armed carrying elements with three, four or more contact weights can be constructed and the individual weights adjusted separately to certain speed stages. I i

The centrifugal governor (Figs. 1 to 5) can naturally also be used for other purposes (railway locomotives, tramcars and similar vehicles).

I claim:

1. In a recording device for speed indicators for motor cars, wherein the recording device has paper feeding means adapted to be driven at different speeds, a source of electric current in communication with an electro-magnet, a recorder including a tracing point bearing on the paper, and means for transmitting movement of the core of the electro-magnet to the tracing point to adjust the position of the point according to the speed of travel of the motor car.

2. A recording device as specified in claim 1, comprising in combination with the tracing point, an oscillatable holder carrying said point and a weight on said point adapted to cause said point to pierce the paper in the event of the motor car coming into sudden collision to register the travelling speed at the instant of the collision.

ALEXANDER SCHMELCHER. 

